1. Field of the Invention
The present invention relates to an image forming apparatus, such as a printer and a multifunctional, and an image forming method that are provided with a plurality of recording-media-supplying trays and are capable of duplex printing on a recording-media supplied by the recording-media-supplying trays.
2. Description of Related Art
In the past, image forming apparatuses, such as printers and multifunctionals, which can print on a recording medium for printing, such as paper, at various print magnification has been developed. For example, a development for forming images with print adjustment for setting a desired print magnification owing to adjustment of scanning rate is disclosed in JP-Tokukai-2002-305653A.
In recent years, image forming apparatuses, such as printers and multifunctional, that is capable of image-forming by xerography have been used, and more elaborate print adjustment (print magnification adjustment, print position adjustment and the like) has been required. In particular, print adjustment for underprint is essential for cases of duplex printing because printing a reverse side after printing a front side causes temperature of a printer sheet at the reverse printing to become higher than that at the front printing and so the size of printer is changed.
The print adjustment generally varies depending on a kind of recording-media for printing. Recently, kinds of recording-media for printing have become diverse (for example, printer sheet, OHP (OverHead Projector) sheet, and so on). Even printer sheet has various kinds used depending on its material, basis weight, size, thickness, coated/uncoated, and the like. Demands for high image quality require setting of print adjustment values depending on the above-described paper types at each print processing.